In 1916, the U.S. Weather Bureau forerunner to the National Weather Service, deployed its first "fire weather mobile unit" to a wildfire. However, onsite weather support to wildfires did not gain widespread acceptance within the fire community until specially equipped Vans were introduced in the late 1930s. Since then, the National Weather Service has periodically infused new technologies to enhance onsite weather forecasting. This paper provides a historical overview of technologies leading up to and including the present day Advanced Technology Meteorological Unit (ATMU). The final section of the paper covers emerging technologies being tested and incorporated into the next generation ATMU.